Blackberry Entremets

Preparation

Step 1 — The blackberry purée

Blend the blackberries with the lemon juice until smooth. Pass through a fine sieve to remove the small seeds. Pour the purée into a saucepan, add 60 g of sugar, and heat over low heat for 5 minutes, stirring. The purée should reduce slightly and thicken. Reserve 100 ml for the glaze and keep the rest for the mousse.

Step 2 — The sponge cake

Prepare a classic ladyfinger sponge: whisk 2 egg yolks with 30 g of sugar until pale. Beat 2 egg whites into stiff peaks with a pinch of salt, then gently fold in 40 g of sifted flour. Spread the batter on a baking sheet lined with parchment paper to a thickness of 1 cm and bake for 10 minutes at 180°C (350°F). Let cool, then cut out a 16 cm disc using the entremets ring.

Step 3 — The blackberry mousse

Soften 5 g of gelatin in a bowl of cold water for 10 minutes. Gently heat the reserved blackberry purée (200 ml) and dissolve the squeezed-out gelatin in it. Let cool slightly. Whip the well-chilled heavy cream into stiff peaks. In another bowl, whisk the mascarpone with 60 g of sugar until smooth. Fold the gelatinized blackberry purée into the mascarpone, then gently fold in the whipped cream, lifting the mixture to keep it airy.

Step 4 — Assembly

Place the entremets ring on a serving plate. Place the sponge disc at the bottom. Pour the blackberry mousse over it, filling the ring three-quarters full. Smooth the surface with a spatula. Refrigerate for at least 3 hours, until the mousse is firm and set to the touch.

Step 5 — The mirror glaze

Soften 3 g of gelatin in cold water. In a saucepan, combine the reserved 100 ml of blackberry purée, 30 g of sugar, and 2 tablespoons of water. Bring to a boil, then remove from heat and add the squeezed-out gelatin, stirring until fully dissolved. Let cool to 32°C (90°F). The glaze should be liquid but warmer than lukewarm. Gently pour the glaze over the well-chilled entremets, starting from the center and letting gravity spread it evenly over the edges.

Step 6 — Finishing

Gently smooth any excess glaze on the edges with a spatula. Return the entremets to the refrigerator for 30 minutes to let the glaze set. Before serving, decorate with fresh blackberries, a few chopped mint leaves, and a light dusting of powdered sugar. Serve well chilled, in clean slices, to reveal the layers of sponge and creamy mousse.